Mise en place

A French term/concept that describes the practice of putting "everything in its place" or "everything ready" while cooking. In a nutshell it means, do all your preparation before hand, and have all your ingredients at room temperature, within reach, and ready to be added to the dish; before you being cooking.

Mise en place plays a large role in stir fry dishes and any dish that requires precise timing. It also relates to a mental practice, determining when and how something is going to be done, before the cooking begins. It is what allows professional cooks, who serve tons of food each night, to perform their job with only a modest amount of stress.